Heater for air tools



April 12, 1966 J. c. (5058 HEATER FOR AIR TOOLS 2 Sheets-Sheet 1 Filed June 2, 1964 INVENTOR. John 62 605s w )M M LU- H/S ATTORNEYS April 12, 1966 J. c. GOSS 3,245,396

HEATER FOR AIR TOOLS Filed June 2, 1964 2 Sheets-Sheet 2 INVENTOR John C 6055 MM,QM+MM HIS ATTORNEYS United States Patent 3,245,396 HEATER FOR AIR TOOLS John C. Goss, Goss Gas, Inc., Glenshaw, Pa. Filed June 2, 1964, Ser. No. 372,045 Claims. (Cl. 126-109) This invention relates to improvements in pressure operated tools and is directed particularly to an apparatus for preventing moisture damage to air operated tools during cold weather.

Many compressed air operated tools, such as air hammers, are commonly employed on outside construction jobs, such as road construction and repair work, where the equipment is exposed to all types of weather. When such construction must be undertaken during the winter months, great difliculties in operating such tools are experienced because moisture in the compressed air freezes in the tools and causes them to jam. Conventional practice has been to inject alcohol into the compressed air lines to prevent the moisture from freezing; however, alcohol cuts the lubricants of the tools and such tools are frequently damaged and destroyed due to a lack of proper lubrication.

My invention is a device that provides heated compressed air to air powered tools used during cold weather. This apparatus interposed between the air compressor and the air operated tool and serves to heat the compressed air before it reaches the tool so as to elevate the temperature of the compressed air and prevent the moisture therein from condensing and freezing while in the tool.

My apparatus may also be conveniently employed to warm or thaw out construction equipment which is exposed to freezing temperatures.

I have shown the present preferred embodiment of my invention in the accompanying drawings in which:

FIGURE 1 is a side elevation of a device falling within the scope of the present invention;

FIGURE 2 is .a plan view of the device of FIGURE 1;

FIGURE 3 is a rear end elevation of the device of FIGURE 1;

FIGURE 4 is a cross-sectional view as seen along the lines IVIV of FIGURE 1;

FIGURE 5 is an enlarged cross-sectional view of the burner arrangement of the device of FIGURE 1; and

FIGURE 6 is an illustrative schematic showing of the utilization of the apparatus of FIGURES 1 through 5.

Referring to the drawings, particularly FIGURES 1 and 2, the present apparatus comprises an elongated housing 10, a chimney 29, a gas burner unit 24, and a loop' shaped conduit 16.

Housing 10 is supported by two sets of legs 11, each comprising transverse beams 12 and angularly positioned leg plates 14.

Free end-s and 22 of conduit 16, which is bent 180 at 18, extend from an open end of housing 10. Conventional air hose connectors 21 are attached to the free ends 20 and 22.

Burner 24 comprises a sleeve-shaped combustion chamber 32, a conventional fuel supply valve 34, and a gas burner tip 36. Chamber 32 is supported by a U-shaped bracket 38 which is attached to and extends from the open end of housing 10. Chamber 32 is attached to bracket 38 so that one open end communicates with the open end of housing 10 above conduit 16. The central axis of chamber 32 is preferably substantially parallel to that of housing 10.

The rear wall 40 of bracket 38 encloses the rear opening of combustion chamber 32. Burner tip 36 consists of a threaded plug 42 which is threadably engaged with a complimentary threaded opening within wall 40. Cenice tral opening 37 of plug 42 receives the supply pipe leading from valve 34 and communicates with the inside of chamber 32 through a restricted orifice 39. Burnable gas flowing through burner tip 36 passes through restricted orifice 39 of plug 42 into the combustion chamber 32.

Air intake holes in the side walls of combustion chamber 32 are preferably arranged in two circumferential rows 44 and 46. The holes of each row are offset so that each hole of row 46 is longitudinally aligned between two holes of row 44 and vice versa. The holes of row 44 nearest plug 42 are preferably of greater diameter than the holes of row 46. A particularly successful burner is one having a six inch diameter combustion chamber with six holes in each row, the holes of row 44 being of about diameter and the holes of row 46 being about A" diameter, and the restricted orifice 39 of plug 42 being about a number 54 drill size.

When burnable gas is emitted into the combustion chamber 32 through burner tip 36, and such gas is ignited, air is drawn into the chamber through the vent holes 44 and 46 to mix with the combustible gas within the chamber 32 and support combustion.

A U-sha-ped guard 52 having one leg attached to each free end 20 and 22 of conduit 16 partially encloses and protects valve 34 of burner 24.

Chimney 29, comprising side Walls 31 and end Walls 33 and 35, communicates with the exhaust end of housing 10 opposite burner 24. Chimney 29 is open at the top and an angularly positioned bafile plate 27 within the chimney deflects heat from burner 24 upwardly and outwardly as indicated by arrow 28 (FIGURE 1).

Handles 50 attached to housing 10 and bracket 38 provide a means for conveniently lifting and positioning my device.

One mode of utilization of my heater is illustrated by FIGURE 6. Free end 20 of the conduit 16 is attached to and in communication with the pressure reservoir 54 of a conventional portable air compressor apparatus 56 through pressure hose 58 and an intervening coiled section of copper tubing 60. The other free end 22 of loopshaped conduit 16 is connected to a conventional air hammer 62 through flexible air hose 64. Bottled gas 66 is supplied to gas burner 24 through a hose 68. Burner 24 is mounted above conduit 16 and a flame 65 (see FIGURE 1) emitted from burner 24 extends into the housing 10 above the conduit. Air pressure from tank 54 will flow through hose 58 and tubing 60 into loopshaped conduit 16 where it will be exposed to heat while within housing 10. The heated air then flows to hammer 62 through air hose 64 to operate hammer 62 while in such a heated condition that moisture within the compressed air will not freeze and damage the tool.

Copper tubing 60 acts as a heat exchanger and prevents heat from Working back from conduit 16 through hose 58 to the air compressor apparatus 56 when the air operated tools are not being used.

Another obvious mode of utilization of my heater is to conduct the heated and compressed air from conduit 16 to a manifold having multiple hose connections along its length. In this manner, a plurality of air operated tools can be simultaneously attached to the manifold so as to be operated on heated air.

Since heat from the flame of burner 24 is conducted upwardly from housing 10 through chimney 29, my heater may be positioned under frozen equipment such as shovels, graders, etc. and the rising heat will thaw such equipment. Alternatively, the heater may be employed to prevent such equipment from freezing.

The burnable gaseous materials supplied to the burner unit 24 will normally be pressurized gas from bottles of liquid propane (LP gas). This source of combustible gas is portable and thus convenient for use in conjunction with my heater. However, any source of commercially available burnable gaseous media is suitable.

While I have described the presently preferred embodirnents of my invention, it is to be understood that it may otherwise be embodied with the scope of the following claims:

I claim:

1. An apparatus for heating compressed air useful for operating an air tool comprising (a) a hollow elongated housing open at at least one end;

(b) a conduit extending into said housing such that both ends thereof extend outwardly from said hous- (c) a gas burner positioned at an open end of said housing to project a flame within said housing and above said conduit;

(d) a first air pressure hose connected to one of said ends of said conduit and to a source of compressed air;

(e) a second air pressure hose connected to the other of said ends of said conduit and adapted to connect to said tool; and

(f) a heat exchanger positioned between said conduit and said source to prevent heat counterfiow to said source in air trapped between said source and said conduit when said tool is nonoperative.

2. The apparatus as described in claim l-in which the heat exchanger is a multi-coiled copper tubing.

3. The apparatus as described in claim 1 in which the heat exchanger includes a continuous length of metal tubing bent into a series of closely spaced axially disposed coils.

4. The apparatus as described in claim 1 wherein said conduit is looped-shaped and extends into said housing such that both ends of said conduit extend outwardly through an open end of said housing.

5. The apparatus as described in claim 1 and having a .chimney at the end of said housing opposite an open end, said chimney being in communication with said housing to exhaust heated air from said housing.

References Cited by the Examiner UNITED STATES PATENTS 2,494,785 1/1950 Tramontini et al. 126--l09 2,532,994 12/1950 Chausse 126-109 X 2,964,033 12/ 1960 Throckmorton et a1. 126-109 3,053,247 9/1962 Bradshaw 1261 10 JAMES W. WESTHAVER, Primary Examiner. 

1. AN APPARATUS FOR HEATING COMPRESSED AIR USEFUL FOR OPERATING AN AIR TOOL COMPRISING (A) A HOLLOW ELONGATED HOUSING OPEN AT AT LEAST ONE END; (B) A CONDUIT EXTENDING INTO SAID HOUSING SUCH THAT BOTH ENDS THEREOF EXTEND OUTWARDLY FROM SAID HOUSING; (C) A GAS BURNER POSITIONED AT AN OPEN OF SAID HOUSING TO PROJECT A FLAME WITHIN SAID HOUSING AND ABOVE SAID CONDUIT; (D) A FIRST AIR PRESSURE HOSE CONNECTED TO ONE OF SAID ENDS OF SAID CONDUIT AND TO A SOURCE OF COMPRESSED AIR; 